The effect of growth parameters on CrN thin films grown by molecular beam epitaxy Y. H. Liu 1 , Kangkang Wang, Wenzhi Lin, Abhijit Chinchore, Meng Shi, Jeongihm Pak and A. R. Smith 1 Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, USA Costel Constantin Department of Physics and Astronomy, James Madison University, 901 Carrier Drive, Harrisonburg, VA 22807, USA Abstract In this paper, we report on the controlling of the effect of growth parameters such as substrate temperature and the ratio of Cr and N atoms on phase formation, surface morphology and crystallization of CrN(001) thin films grown by plasma-assisted molecular beam epitaxy on the MgO(001) substrate. The reflected high energy electron diffraction, atomic force microscopy, X-ray diffraction and scanning tunneling microscopy are used to characterize the thin films grown under various conditions. High-quality CrN(001) thin films are achieved at a substrate temperature 430 o C with a low Cr deposition rate. Keywords: A. Chromium nitride B. Crystalline orientation C. Molecular beam epitaxy D. Scanning tunneling microscopy E. Reflection high energy diffraction F. X-ray diffraction 1. Introduction CrN has attracted much attention in last two decades not only because of its high me- chanical hardness and good corrosion resistance, but also because of its intriguing magnetic and electronic properties. For example, CrN is paramagnetic at room temperature and with the lowering of the temperature, an anti-ferromagnetic phase appears at 260-286 K, depending on the atom ratio of Cr and N, which has been accepted by most groups [1, 2]. The electronic transport properties were extensively investigated on CrN samples in the forms of compressed poly-crystalline pellets [1], poly-crystalline films [2] and single-crystal films [3] grown by solid-state sintering, sputtering technique, pulsed laser deposition [4] and molecular beam epitaxy (MBE) [5, 6]. However, the controversy still remains on its 1 Corresponding authors. Y. H. Liu, present address: MPA-CINT, MS K771, Los Alamos National Laboratory, NM 87545, email address: yhaoliu76@gmail.com; A. R. Smith, Tel: +1-740-597-2576; fax: +1-740-593-0433. email address: smitha2@ohio.edu Preprint submitted to Thin Solid Films August 6, 2011